A circle has 360 degrees. Each degree can have 60 minutes (designated as ' ) and each minute can have 60 seconds (designated as " ). Since we can not convert minutes or seconds into radians directly we need to convert the minutes and seconds into a decimal number. Here is the formula:

A radian is the angle subtended at the centre of a circle by an arc of its circumference equal in length to the radius of the circle. Since we know that that the formula for the circumference of a circle is we can determine that there are radians in a circle. We abbreviate radians as rad.

Mathematics requires us to use radians for most angular measurments. Therefore we need to know how to convert from degrees to radians Since we know that there are degrees or radians in a circle. We can determine these equations: